We are implementing Google Checkout and Paypal Checkout on our site as options to the regular checkout process. We are trying to figure out which way to go with this.
1/ From the main shopping cart page, the customer can select Google Checkout, PayPal or the normal credit card checkout on the site. If they choose Paypal or Google Checkout they bypass all the site checkout pages, enter their Google/PayPal information and easily checkout. The pros to this are that they don't have to go through the process of entering all their information through our checkout process. The con is that we can get their specific email address and allow then to opt-in to multiple newsletters. Paypal/Google Checkout do have opt-ins through their services though I don't know what kind of sign-up rate we would have.
2/ They go through our checkout process until they reach the billing information page, where they have the options to pay by credit card right on the site, use PayPal or use Google Checkout. The pros I see to this are that we get to have all the custom information in our database (email address specifically, as we give options for different newsletters to signup for, something that can't be done through Google Checkout or PayPal, though they do have options for one mailing list to be sent to the seller), the con being they have to enter all their information and then enter their Paypal or Google Checkout information again.
So my question is whether customers mind going through the site checkout process and then paying by PayPal/Google Checkout, or do they like using PayPal/Google Checkout instead because they don't have to enter in all their information every time they buy something online.
Any results you have seen or advice would be helpful.